This invention relates to unit dose laundry compositions for softening or conditioning fabrics. More particularly, this invention relates to unit dose liquid fabric softening compositions, which is contained in a water-soluble container suitable for use in an automatic washing machine.
Detergent compositions manufactured in the form of compacted detergent powder are known in the art. U.S. Pat. No. 5,225,100, for example, describes a tablet of compacted powder comprising an anionic detergent compound, which will adequately disperse in the wash water.
Although detergent compositions in the form of compacted granular tablets of various shapes have received much attention in the patent literature, the use of such tablets to provide a unit dose fabric softener which will soften or condition fabrics in the wash cycle without impairing detergency or otherwise compromise the cleaning benefits provided by the detergent composition is not known.
Laundry detergent compositions which further include a fabric softener to provide softening or conditioning of fabrics in the wash cycle of the laundering operation are well-known in the art and described in the patent literature. See, for example, U.S. Pat. No. 4,605,506 to Wixon; U.S. Pat. No. 4,818,421 to Boris et al. and U.S. Pat. No. 4,569,773 to Ramachandran et al., all assigned to Colgate-Palmolive Co., and U.S. Pat. No. 4,851,138 assigned to Akzo. U.S. Pat. No. 5,972,870 to Anderson describes a multi-layered laundry tablet for washing which may include a detergent in the outer layer and a fabric softener, or water softener or fragrance in the inner layer. But, these type of multi-benefit products suffer from a common drawback, namely, there is an inherent compromise which the user necessarily makes between the cleaning and softening benefits provided by such products as compared to using a separate detergent composition solely for cleaning in the wash cycle and a separate softening composition solely for softening in the rinse cycle. In essence, the user of such detergent softener compositions does not have the ability to independently adjust the amount of detergent and softener added to the wash cycle of a machine in response to the cleaning and softening requirements of the particular wash load.
Some attempts have been made in the art to develop wash cycle active fabric softeners, typically in powder form. But, these type products are characterized by the same inconvenience inherent with the use of powered detergents, namely, problems of handling, caking in the container or wash cycle dispenser, and the need for a dosing device to deliver the desired amount of active softener material to the wash water.
The use of a unit dose fabric softening composition contained in a water soluble container such as a sachet offers numerous advantages. To be effective, the unit dose fabric softening compositions, contained in a sachet, must be able to disperse in the wash liquor in a short period of time to avoid any residue at the end of the wash cycle.
Typically, the wash cycle time can be as short as 12 minutes and as long as 90 minutes (in typical European washers) depending on the type of washer and the wash conditions. Therefore, the water-soluble sachet must be soluble in the wash liquor before the end of the cycle.
The present invention provides a unit dose fabric softening composition contained in a water soluble container for softening or conditioning fabrics in an automatic washing machine, said unit dose comprising (a) a wash soluble container; and (b) disposed in the water soluble container is a nonaqueous liquid fabric softener composition, the amount of composition being sufficient to form a unit dose capable of providing effective softening or conditioning of fabrics in said washing machine.
The term xe2x80x9cfabric softenerxe2x80x9d is used herein for purposes of convenience to refer to materials which provide softening and/or conditioning benefits to fabrics in a home or automatic laundering machine.
The fabric softener composition of the invention is preferably comprised of one or more fabric softening agents, optionally a dispersing agent, and optionally a perfume.
In accordance with the process aspect of the invention there is provided a process for softening or conditioning laundry which comprises contacting the laundry with an effective amount of the unit dose laundry composition defined above.